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A225066
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Least hexagonal number that is the product of n hexagonal numbers greater than 1.
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7
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6, 2850, 79800, 2162160, 134734320, 15518903400, 174626020800, 19794628854000, 659394533191680, 659394533191680, 659394533191680, 38022361747469489295360
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OFFSET
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1,1
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LINKS
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EXAMPLE
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Let hex(n) = n*(2n-1). Then
a(1) = 6 = hex(2).
a(2) = 2850 = hex(38) = hex(3) * hex(10).
a(3) = 79800 = hex(200) = hex(3) * hex(4) * hex(10).
a(4) = 2162160 = hex(1040) = hex(2)^2 * hex(4) * hex(33).
a(5) = 134734320 = hex(8208) = hex(2)^2 * hex(3) * hex(4) * hex(67).
a(6) = 15518903400 = hex(88088) = hex(2) * hex(3) * hex(6)^2 * hex(7) * hex(15).
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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Corrected a(6) and added a(7)-a(12) by Lars Blomberg, Sep 21 2013
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STATUS
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approved
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